• Korean Journal of Fisheries and Aquatic Sciences
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• v.21 no.1
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• pp.21-29
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• 1988

This study was carried out to develop the powdered Katsuobushi (a kind of boiled, smoked, and dried fish product which is used for seasoning soup as it is.) using skipjack as a natural flavoring substance. The processing conditions of the powdered Katsuobushi and the changes of taste compounds during processing of the products were examined. In preparation of the powdered Katsuobushl, frozen skipjack was thawed, beheaded, gutted, filleted and then sliced to 1cm of thickness. The silted meats were boiled in skipjack extract for 20 minutes, and then it was smoked for, 3 times to $10\~12\%$ moisture content at $80^{\circ}C$ for 8 hours. The smoked - dried meats were followed to be 50 mesh of particle size. The effect of slicing and boiling in skipjack meat extract on enhancing flavor and on preventing lipid oxidation of product during processing were observed. The moisture content and crude lipid content of the powdered Katsuobushi was in the range of 11 to $12\%$ and 4.3 to $4.8\%$, respectively. The taste compounds of the product were nucleotides and their related compounds, 1135.8mg/100g ; free amino acid and related compounds, 2210.2mg/100g ; non-volatile organic acids, 1148.0mg/100g ; and total creatinine. 592.1mg/100g on dry basis, and small amount of betaine and TMAO. The major elements of mineral in the product were found to be K, Mg, Na, and Ca. The content of IMP was 542.0mg/100g, and major free amino acids were found to be histidine, anserine, taurine, carnosine and alanine of which occupied to $83.6\%$ of total free amino acids. In non -volatile organic acids, major ones were lactic acid, succinic acid, pyroglutamic acid and $\alpha-ketoglutaric$ acid. From the results of the chemical experiments and sensory evaluation, we may conclude that the flavor of the product from present experiment is more desirable than that of conventional products although the processing time used were much shortened than that of conventional method, and it can be commercialized as a seasoning powder.

• Food Science of Animal Resources
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• v.29 no.1
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• pp.24-33
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• 2009

This study investigated the microbial contamination levels of raw meats used for short-ripened salami and changes in the microbial and physico-chemical properties of the product during storage at 10 and $25^{\circ}C$ for up to 120 days. The microbial counts of raw meats ranged between 2 and 4 Log CFU/g. Frozen-thawed sow meat showed higher total aerobe and Enterobacteriaceae counts than fresh chilled pork and pork back fat. Staphylococcus aureus was found in all raw materials except fresh chilled pork samples, and Clostridium perfringens was detected in a sample stored for 21 days at $25^{\circ}C$. The counts of total aerobes, lactic acid bacteria and Staphylococcus spp. decreased more rapidly at $25^{\circ}C$ than at $10^{\circ}C$ when the storage time was extended. The growth of Enterobacteriaceae, Pseudomonas spp., Clostridium spp., yeast, and mold were restricted to levels below 2 Log CFU/g during storage. The contents of salt, water, crude protein, crude fat, and ash of salami samples were 3.4, 33.4, 30.8, 32.7, and 4.3%, respectively, which were not affected by storage time or temperature. The pH value of the salami was initially 4.79 and increased to 5.02 and 5.26 after 120 days of storage at 10 and $25^{\circ}C$, respectively, whereas the water activity values decreased from an initial value of 0.91 to 0.90 and 0.88 after 120 days at 10 and $25^{\circ}C$, respectively. The TBA and VBN values increased slowly during storage. The redness value of the salami samples stored at $25^{\circ}C$ decreased more significantly than the samples stored at $10^{\circ}C$. With increased storage time, the values for the rheological characteristics of the salami in terms of hardness, brittleness, elasticity, cohesiveness, gumminess, and adhesiveness tended to decrease more remarkably at $25^{\circ}C$ than at $10^{\circ}C$. Based on sensory evaluation scores, it appears that short-ripened salami is no longer acceptable after 90 days at $10^{\circ}C$ and 30 days at $25^{\circ}C$.

• Food Science and Preservation
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• v.30 no.1
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• pp.88-97
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• 2023

As livestock consumption in Korea has been gradually increasing, the quality of the final products has been improved to meet this increased demand. In particular, maintaining the water holding capacity (WHC) and minimizing the drip loss during the thawing of frozen meat are of utmost importance. This study investigated the physicochemical properties of frozen pork subjected to thawing under different conditions: at room temperature (20℃, under air), at a low temperature (4℃ refrigerator, under air), under water (20℃, under water in a vacuum bag), under microwave (microwave-thawing, 260 W), and under low-pressure tumbling (20℃, 0.015 bar, tumbling). The shortest thawing time for frozen pork was recorded upon low-pressure tumbling thus indicating a fast heat transfer. The lowest drip loss (0.2%) and highest WHC (94.5%) were also recorded under this condition. A significantly higher drip loss was observed upon microwave- (1.0%) and water-thawing (1.2%), which resulted in the lowest WHC in microwave thawing (87.2%). The highest total count of aerobic bacteria and coliform group were observed upon room temp thawing while the low pressure tumbling and thawing resulted in the lowest aerobic bacteria (1.90 log CFU/g) and coliform (0.78 log CFU/g) count. Consequently, thawing by low pressure tumbling afforded the best food quality.